Steve,
What about putting the whole " Variable Geometrie " in a protected
environment, such as a light air pressure. The envelop could be some kind
of reenforced Mylar already used fot baloons........
Make me think about those big Boeings equiped with Awacs Radar, that isn't
science fiction.
Quite sure there must be some twisted weird who thought about this before.
Funny to have a flying saucer on top of the tower.
Jos
----- Original Message -----
From: "Steve Katz" <stevek@jmr.com>
To: "'on4kj'" <on4kj@skynet.be>; <Jim@shawresources.com>; "Jon Ogden"
<na9d@speakeasy.net>; "Dino Darling" <k6rix@arrl.net>;
<towertalk@contesting.com>
Sent: Thursday, November 14, 2002 11:21 PM
Subject: RE: [Towertalk] LPDAs...
> Hi Jos,
>
> I'm all for it, and recommended this already. I don't have the bandwidth
> for such a project myself, nor am I a mechanical engineer; however I'm
> certain such expertise exists, possibly right here on this reflector!
>
> I'm not sure how to make an affordable telescoping boom that will
withstand
> operation in ice and snow, but it can probably be done. Maybe pneumatics!
> I can hear it now, "Hold on George, I have to change bands...let me open
> this big valve...whoooooosh...."
>
> WB2WIK/6
>
> "If everything seems under control, you're just not going fast enough." -
> Mario Andretti
>
> > -----Original Message-----
> > From: on4kj [SMTP:on4kj@skynet.be]
> > Sent: Thursday, November 14, 2002 2:39 PM
> > To: Steve Katz; Jim@shawresources.com; Jon Ogden; Dino Darling;
> > towertalk@contesting.com
> > Subject: Re: [Towertalk] LPDAs...
> >
> >
> > The SteppIR can obviously be adjusted to make a beam pattern over an
> > octave
> > or more, and to create a good match to its feedline, by infinitely
varying
> > all the element length combinations; but it will never be optimized on
> > more
> > than one band because of the fixed element spacing.
> > -------------------------------------------
> >
> > Steve,
> >
> > Why should one not realize a boom with mobil elements.
> > Its not impossible, just find a good team totake up the challenge.
> > After all radio amateur activity is not only commercial business, pseudo
> > chicken band.
> > What say !
> > Jos on4kj
> >
> >
> >
> > > Can't comment on SteppIR wind/WX survivability, etc, since I don't
think
> > any
> > > have been up long enough yet. In a few years, we'll know more on that
> > one!
> > >
> > > -WB2WIK/6
> > >
> > > "If everything seems under control, you're just not going fast
enough."
> > -
> > > Mario Andretti
> > >
> > > > -----Original Message-----
> > > > From: Jim Shaw [SMTP:Jim@shawresources.com]
> > > > Sent: Thursday, November 14, 2002 8:52 AM
> > > > To: Jon Ogden; Dino Darling; towertalk@contesting.com
> > > > Subject: RE: [Towertalk] LPDAs...
> > > >
> > > > QUESTION: Instead of an LPDA, why not use a 3 element SteppIR
> > antenna?
> > > > Don't they cover all frequencies continuously from 13.9 to 30 MHz?
> > Isn't
> > > > that similar to the design goal of an LPDA? Seems like a SteppIR
> > should
> > > > easily cover MARS frequencies in that range. Just asking cause I
have
> > no
> > > > first hand experience with either and LPDA or a SteppIR.
> > > >
> > > >
> > > > 73 de Jim WA6PX
> > > > JGShaw@Alumni.HAAS.org
> > > >
> > > > -----Original Message-----
> > > > From: towertalk-admin@contesting.com
> > > > [mailto:towertalk-admin@contesting.com]On Behalf Of Jon Ogden
> > > > Sent: Thursday, November 14, 2002 6:41 AM
> > > > To: Dino Darling; towertalk@contesting.com
> > > > Subject: Re: [Towertalk] LPDAs...
> > > >
> > > >
> > > > on 11/14/02 12:17 AM, Dino Darling at k6rix@arrl.net wrote:
> > > >
> > > > > I learned more about LPDA's from this article than anything I've
> > read
> > to
> > > > > date! I will have to re-read the article myself, but I remember
> > talk
> > > > about
> > > > > front-to-back figures that were BETTER than a small yagi.
> > > >
> > > > I could believe they have better F/B than a small Yagi. I also
> > believe
> > > > that
> > > > a good sized LPDA would outperform a small beam. However, I am not
> > > > completely sold on the idea of absolutely better performance.
> > > >
> > > > I'll have to look into it since I am currently perusing what sort of
> > > > antenna
> > > > to get to replace my TA-33.
> > > >
> > > > 73,
> > > >
> > > > Jon
> > > > NA9D
> > > >
> > > > -------------------------------------
> > > > Jon Ogden
> > > > NA9D (ex: KE9NA)
> > > >
> > > > Citizen of the People's Democratic Republik of Illinois
> > > >
> > > > Life Member: ARRL, NRA
> > > > Member: AMSAT, DXCC
> > > >
> > > > http://www.qsl.net/na9d
> > > >
> > > > "A life lived in fear is a life half lived."
> > > >
> > > >
> > > > _______________________________________________
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> > > See http://www.mscomputer.com
> > >
> > > Wireless Weather Stations now $349.95. Call Toll Free,
> > > 888-333-9041 for additional information.
> > > _______________________________________________
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> > >
> >
> _______________________________________________
> AN Wireless Self Supporting Towers at discounted prices,
> See http://www.mscomputer.com
>
> Wireless Weather Stations now $349.95. Call Toll Free,
> 888-333-9041 for additional information.
> _______________________________________________
> Towertalk mailing list
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>
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